You can configure the MPC to take a value in the range 0 through 5 for the policer tick byte by using the policer-limit statement at the [edit chassis] hierarchy level. If this statement is not configured, the policer tick byte can take values till 7, which is the default behavior. You can use the set chassis policer-limit command to enable this feature.
You must restart the MPC or the router for the changes to take effect.